1. Field of the Invention
This invention relates generally to respiratory apparatus, and more particularly to a face mask with means for tempering cold air for breathing.
2. Description of the Prior Art
It has been known for a long time that inhalation of cold air can be detrimental to health, the degree of detriment depending upon how much and how cold is the air, and the condition of the individual breathing it. In an effort to minimize the impact of low air temperature conditions, individuals living, working, and exercising have employed various devices in the past to minimize the impact of cold air. Such devices have ranged from simple scarfs to relatively simple face masks, to elaborate masks or breathing systems. Examples of some simple masks are shown in U.S. patents as follows: U.S. Pat. No. 3,333,585, Barghini et al., Aug. 1, 1967; U.S. Pat. No. 3,814,094, June 4, 1974, DeAngelis et al.; U.S. Pat. No. 4,325,365, Barbuto, Apr. 20, 1982; U.S. Pat. No. 4,136,691, Ebeling et al., Jan. 30, 1979; U.S. Pat. No. 4,196,728, Granite, Apr. 8, 1980.
More complex apparatus for the same purpose can be found in the following patents: U.S. Pat. No. 2,610,038, Phillips, Sept. 9, 1952; U.S. Pat. No. 3,326,214, June 20, 1967, McCoy; U.S. Pat. No. 3,249,108, May 3, 1966, Terman; U.S. Pat. No. 4,245,631, Wilkinson and Brown, Jan. 20, 1981. Phillips discloses use of exhaled air moisture storing means capable of returning heat and moisture to the incoming air. The McCoy apparatus is a more compact type using a different style of heat exchange element. The Terman patent is more elaborate in that it employs an electric heater in the mask and which is supplied with power from a rechargeable battery carried in a jacket pocket. The Wilkinson and Brown patent also has an electric heating element 40. It combines both the electric heating element and storage of heat from previously inhaled air, to heat subsequently inhaled air. Other devices are known for heating inhaled air. Bjurstrom U.S. Pat. No. 1,982,412 has a heater for use in therapy. It is intended for use in a building environment where one has access to an electric outlet.
Devices intended primarily for use by divers and heating heat and moisture regenerating means for tempering breathing mixtures are as follows: U.S. Pat. No. 3,747,598, Cowans, July 24, 1973 and U.S. Pat. No. 4,201,206, Kuehn et al., May 6, 1980. Apart from apparatus for treating cold air inhaled, there is a heated nasal inhaler U.S. Pat. No. 2,410,903 issued Nov. 12, 1946 to M. A. Rogge. A humidity exchanger is shown in U.S. Pat. No. 4,048,993 for use in anesthesia. A heat and moisture exchanger for use in anesthesia and artificial respiration is shown in U.S. Pat. No. 4,090,513 issued May 23, 1978 to Togawa. There remains a need for a simple apparatus optimizing the use of materials that enhance the performance of apparatus with a given power supply. The present invention is addressed to meeting that need.